DWARF: Avoid cross-CU references under Fission

Turns out that the Fission/Split DWARF package format (DWP) is currently
insufficient to handle cross-CU (ref_addr) references. So for now,
duplicate any debug info needed in these situations:
* inlined_subroutine's abstract_origin
* inlined variable's abstract_origin
* types

Keep the ref_addr behavior in general, including in the split DWARF
inline debug info that can be emitted into the object files for online
symbolication.
Keep a flag to use the old (ref_addr) behavior for testing ways of
addressing this limitation in the DWP tool (& for those not using DWP
packaging).

llvm-svn: 302858

1 files changed, 9 insertions, 11 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 8a96e7867b6..b9c5aa9ffb2 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -210,7 +210,6 @@ class DwarfDebug : public DebugHandlerBase {
   DenseMap<const MCSymbol *, uint64_t> SymSize;
 
   /// Collection of abstract variables.
-  DenseMap<const MDNode *, std::unique_ptr<DbgVariable>> AbstractVariables;
   SmallVector<std::unique_ptr<DbgVariable>, 64> ConcreteVariables;
 
   /// Collection of DebugLocEntry. Stored in a linked list so that DIELocLists
@@ -313,20 +312,16 @@ class DwarfDebug : public DebugHandlerBase {
 
   typedef DbgValueHistoryMap::InlinedVariable InlinedVariable;
 
-  /// Find abstract variable associated with Var.
-  DbgVariable *getExistingAbstractVariable(InlinedVariable IV,
-                                           const DILocalVariable *&Cleansed);
-  DbgVariable *getExistingAbstractVariable(InlinedVariable IV);
-  void createAbstractVariable(const DILocalVariable *DV, LexicalScope *Scope);
-  void ensureAbstractVariableIsCreated(InlinedVariable Var,
+  void ensureAbstractVariableIsCreated(DwarfCompileUnit &CU, InlinedVariable Var,
                                        const MDNode *Scope);
-  void ensureAbstractVariableIsCreatedIfScoped(InlinedVariable Var,
+  void ensureAbstractVariableIsCreatedIfScoped(DwarfCompileUnit &CU, InlinedVariable Var,
                                                const MDNode *Scope);
 
-  DbgVariable *createConcreteVariable(LexicalScope &Scope, InlinedVariable IV);
+  DbgVariable *createConcreteVariable(DwarfCompileUnit &TheCU,
+                                      LexicalScope &Scope, InlinedVariable IV);
 
   /// Construct a DIE for this abstract scope.
-  void constructAbstractSubprogramScopeDIE(LexicalScope *Scope);
+  void constructAbstractSubprogramScopeDIE(DwarfCompileUnit &SrcCU, LexicalScope *Scope);
 
   void finishVariableDefinitions();
 
@@ -446,7 +441,8 @@ class DwarfDebug : public DebugHandlerBase {
                          const DbgValueHistoryMap::InstrRanges &Ranges);
 
   /// Collect variable information from the side table maintained by MF.
-  void collectVariableInfoFromMFTable(DenseSet<InlinedVariable> &P);
+  void collectVariableInfoFromMFTable(DwarfCompileUnit &TheCU,
+                                      DenseSet<InlinedVariable> &P);
 
 protected:
   /// Gather pre-function debug information.
@@ -518,6 +514,8 @@ public:
   /// split dwarf proposal support.
   bool useSplitDwarf() const { return HasSplitDwarf; }
 
+  bool shareAcrossDWOCUs() const;
+
   /// Returns the Dwarf Version.
   uint16_t getDwarfVersion() const;